In a Gas-to-Liquids (GTL) plant, a Fischer-Tropsch process may be used to produce waxy hydrocarbons (typically called Syncrude) which are then converted, or upgraded, into various GTL fuels downstream, including, for example, diesel, naphtha, etc. Unfortunately, the Fischer-Tropsch process also produces waste water, which contains organic compounds, such as hydrocarbons, alcohols, acids, etc. This effluent must be treated to remove the organic compounds—thereby increasing overall production costs.
In one example, a Fischer-Tropsch reactor is fed with synthesis gas, which is a mixture of hydrogen and carbon monoxide. While synthesis gas may be generated using a number of different schemes, hydrocarbon feedstock, such as natural gas, is typically fed into a synthesis gas reactor, or reformer, which produces synthesis gas for the Fischer-Tropsch reactor.
The reformer requires steam for the reforming reactions, and this steam may be introduced into the hydrocarbon feedstock, for example, by a steam header and/or steam that is generated within a saturator. Of course, makeup water must be supplied to produce this steam—thereby increasing overall production costs as well.